HIV实验室检测及其研究进展

目的:艾滋病又称获得性免疫缺陷综合征(AIDS),由人类免疫缺陷病毒(HIV,又称艾滋病病毒)引起,是危胁人类健康甚至导致死亡的一种严重传染病,其实验室检测方法需要进一步探讨。方法:本文从常用HIV检测方法及HIV检测新进展两个方面总结了HIV实验室检测及进展。结果:HIV的实验室检测是预防AIDS的主要方法,可直接影响到AIDS的筛查及诊治。结论:在经历20多年后,HIV的实验室检测法有了飞跃的发展,如今的HIV的实验室检测目标聚焦在如何开发更加准确、更加敏感、更加快速、更加简单化、更加自动化几个方向上,其研究任重而道远,需要我们共同努力携手完成。     

Improved injection safety after targeted interventions in the Syrian Arab Republic

OBJECTIVES: Concerns about unsafe injection practices and possible infections with blood-borne pathogens in the Syrian Arab Republic motivated an assessment of the injection safety situation in the country in July 2001. In light of the recommendations from this assessment, the Ministry of Health of Syria, with the assistance of WHO, implemented a set of activities under the 'Focus Project', which aims to ensure immunization safety. The first phase of the project ran from May 2002 to February 2004, and consisted of the improved provision of injection safety equipment and supplies, the elaboration and wide distribution of national guidelines on injection safety and safe waste management, a behaviour change and communication campaign targeting the general public, and comprehensive training of healthcare workers. A follow-up survey was carried out in February 2004, 2 years after initiation of the project. METHODS: Two representative surveys were conducted using a standardized assessment tool. A cluster sampling strategy, with probability proportionate to the population size, led to the inclusion of 80 health facilities in eight districts in 2001 and of 120 health facilities in 12 districts in 2004. RESULTS: Injection practices had significantly improved 2 years after the start of the project. The 2001 study had pointed to a low, but non-negligible risk to patients (2% unsafe injections), coupled with a high risk to healthcare workers (61% reported needle-stick injuries in the last 12 months) and to the communities owing to unsafe waste disposal (sharps waste found outside 37% of health facilities, waste disposal considered unsafe in 48% of them). The 2004 survey showed that 90% of Syrian healthcare workers had received training in injection safety. All injections observed were given safely (difference to 2001 not significant), although some problems in preparation and reconstitution prevailed. The risk to healthcare workers was significantly reduced as only 14% of the staff reported needle-stick injuries (p < 0.001). The risk to the communities was notably decreased following improvements in sharps waste management (sharps were found in the surroundings of only 13% of health facilities, p < 0.001). CONCLUSIONS: The example of Syria shows that rapid improvement in injection safety is possible and that the necessary tools and methods to monitor and evaluate progress are at our disposal. Challenges remain in transferring this successful programme from the well-structured immunization programme to the more diverse curative health services.     

Genetic,molecular and functional analyses of complement factor I deficiency

Complete deficiency of complement inhibitor factor I (FI) results in secondary complement deficiency due to uncontrolled spontaneous alternative pathway activation leading to susceptibility to infections. Current genetic examination of two patients with near complete FI deficiency and three patients with no detectable serum FI and also close family members revealed homozygous or compound heterozygous mutations in several domains of FI. These mutations were introduced into recombinant FI and the resulting proteins were purified for functional studies, while transient transfection was used to analyze expression and secretion. The G170V mutation resulted in a protein that was not expressed, whereas the mutations Q232K, C237Y, S250L, I339M and H400L affected secretion. Furthermore, the C237Y and the S250L mutants did not degrade C4b and C3b as efficiently as the WT. The truncated Q336x mutant could be expressed, in vitro, but was not functional because it lacks the serine protease domain. Furthermore, this truncated FI was not detected in serum of the patient. Structural investigations using molecular modeling were performed to predict the potential impact the mutations have on FI structure. This is the first study that investigates, at the functional level, the consequences of molecular defects identified in patients with full FI deficiency.     

Hypomorphic mutation of ZAP70 in human results in a late onset immunodeficiency and no autoimmunity

Complete lack of function of the tyrosine kinase ZAP70 in humans results in a severe immunodeficiency, characterized by a lack of mature CD8⁺ T cells and non‐functional CD4⁺ T cells. We report herein an immunodeficiency with an inherited hypomorphic mutation of ZAP70 due to a single G‐to‐A substitution in a non‐coding intron. This mutation introduces a new acceptor splice site and allows low levels of normal alternative splicing and of WT ZAP70 expression. This partial deficiency results in a compromised TCR signaling that was totally restored by increased expression of ZAP70, demonstrating that defective activation of the patient T cells was indeed caused by the low level of ZAP70 expression. This partial ZAP70 deficiency was associated with an attenuated clinical and immunological phenotype as compared with complete ZAP70 deficiency. CD4⁺ helper T‐cell populations including, follicular helper T cells, Th1, Th17 and Treg were detected in the blood. Finally, the patient had no manifestation of autoimmunity suggesting that the T‐cell tolerogenic functions were not compromised, in contrast to what has been observed in mice carrying hypomorphic mutations of Zap70. This report extends the phenotype spectrum of ZAP70 deficiency with a residual function of ZAP70.     

Impacto y características de la gripe nosocomial a lo largo de 10 temporadas en un hospital universitario de tercer nivel

ObjectivesTo analyze the characteristics of patients with nosocomial flu, to compare them with patients with community-acquired influenza to study possible differences and to identify possible risk factors associated with this type of flu.Patients and methodsObservational, cross-sectional and retrospective study of hospitalized patients with a microbiological confirmation of influenza in a third-level university hospital over 10 seasons, from 2009 to 2019. Nosocomial influenza was defined as that infection whose symptoms began 72 h after hospital admission, and its incidence, characteristics and consequences were further analyzed.ResultsA total of 1260 hospitalized patients with a microbiological diagnosis of influenza were included, which 110 (8.7%) were nosocomial. Patients with hospital-acquired influenza were younger (71.74 ± 16.03 years, P = 0.044), had a longer hospital stay (24.25 ± 20.25 days, P < 0.001), had more frequently a history of chronic pulmonary pathologies (P = 0.010), immunodeficiency (P < 0.001), and were associated with greater development of bacterial superinfection (P < 0.001), respiratory distress (P = 0.003), and admission to the intensive care unit (ICU) (P < 0.001). In the multivariate logistic regression analysis, the following characteristics were identified as independent risk factors: immunodeficiency (ORa = 2.33; 95% CI: 1.47-3.60); ICU admission (ORa = 4.29; 95% CI: 2.23-10.91); bacterial superinfection (ORa = 1.64; 95% CI: 1.06-2.53) and respiratory distress (ORa = 3.88; 95% CI: 1.23-12.23).ConclusionsNosocomial influenza is more common in patients with a history of immunodeficiency. In addition, patients with hospital-acquired influenza had an increased risk of bacterial superinfection, admission to the ICU, and development of respiratory distress.     

HIV mass screening of infants and mothers: historical, technical, and practical issues

Screening groups of anonymous infants for HIV antibody, as an index of maternal infection rates, has been a widely used seroepidemiological method since being introduced in 1986 in Massachusetts (USA). One shortcoming has been the applicability only to parturient women, thus necessitating corrections for fertility rates in extrapolation to all women. A second disadvantage has been controversy and confusion about the distinction between anonymous seroprevalence studies and linked testing. However, there have been major advantages such as the "leading indicator" nature of the data obtained. Experience with screening nearly a half million Massachusetts newborns through December 1992 has shown seroprevalence rates stabilizing at 2.4 per 1000, and with consistent 10-fold differences between groups of birth hospitals serving different socio-economically defined populations. In addition to predicting the future of the AIDS epidemic in children, the information provides a reference point for comparing the completeness of targeted identifications of HIV infection in mothers and infants.     

Usefulness of chest physiotherapy with Positive Expiratory Pressure (PEP)-mask in HIV-infected children with recurrent pulmonary infections

Eight children with human immunodeficiency virus (HIV) and recurrent bacterial pulmonary infections were treated using a Positive Expiratory Pressure (PEP)-mask twice a day for 12 months. At the end of the study, a reduction in the number of pulmonary infections [mean (SD) 2. 1 (0. 9) vs 4. 5 (1) p < 0. 0001] and antibiotic courses [mean (SD) 1. 5 (0. 7) vs 2. 4 (0. 9) p < 0. 021] was noted. The PEP-mask is a chest physiotherapy technique for removing infected secretions and optimizing airway functions that is also useful in HIV-infected children.     

The development of virus-free labile blood derivatives — A review

Human blood plasma derived coagulation factor concentrates carry a substantial risk of virus transmission as traditionally prepared. Intensive investigations during the past 5 years have led to the development of several virus sterilization procedures which can be applied to these concentrates as well as to other labile protein derivatives. This review summarizes detailed information which is now available establishing the virucidal potency of these procedures, particularly with regard to the contaminating viruses of most concern: hepatitis B, non-A, non-B hepatitis and the AIDS virus.Currently utilized virus sterilization procedures have greatly reduced or eliminated the transmission of AIDS virus, HIV. The transmission of non-A, non~B hepatitis virus (NANBHV) has also been greatly reduced by some but not all of these procedures. Additional virus safety data in man will be required to establish whether any of the procedures gives products which arc totally safe from NANBHV transmission and to assess their impact on other blood-borne-viruses.Corresponding author.